\begin{tikzpicture}[>=Stealth, scale=0.5,
    every node/.style={fill=white, inner sep=1pt},
]
    \draw [->] (-3, 0) -- (3, 0) node[below=0.2em] {$x$};
    \draw [->] (0, -3) -- (0, 3) node[left=0.2em]  {$y$};
    \draw (0, 0) node [below left=0.3em] {\small $O$};

    \draw[very thick, domain=-2:2, samples=5] plot (\x, {-1.3*\x});
\end{tikzpicture}

